The delta of Ecuadors Guayas River and nearby tributaries contain the largest expanse of mangroves in the country. This forested labyrinth of tidal channels and low-lying islands is a crucial ecosystem. It teems with wildlife, soaks up floodwater and banks vast amounts of planet-warming carbon.
But the delta is also the site of the countrys largest metropolitan area, a collection of cities and towns home to 3 million people. Here, large areas of forest have made way for urban sprawl and hundreds of shrimp farms.
Now a project backed by the United Nations Environment Programme (UNEP) aims to demonstrate that mangrove ecosystems and urban development can go hand in hand. City teams have planted thousands of mangroves around the delta municipality of Samborondn, the first step in what some hope will be a bigger push to protect local settlements from increasingly extreme weather.
Coastal towns and cities face a mounting threat from climate change, which in many places is spawning more frequent and intense storms, says Mirey Atallah, Chief of the Adaptation and Resilience Branch in UNEPs Climate Change Division. Science has shown that mangroves are a cost-effective way to blunt those impacts, saving lives and property alike. That role cannot be underestimated.
Coastal defences
Mangroves a collection of salt-tolerant trees and bushes fringe more than 2 million kilometres of coastlines and inter-tidal zones around the world. Found mostly in the tropics and sub-tropics, they provide a first line of defence against storm surges, currents, waves and tides growing threats as climate change leads to rising sea levels. Their intricate root system also makes them a haven for fish and other organisms seeking shelter, food and reproductive grounds. This diversity of life makes mangroves vital to the fisheries on which many coastal communities depend.
But mangroves have often been sacrificed in the face of development, whether for farming, aquaculture or settlements. The total area of mangroves worldwide fell by more than 5,000 square kilometres, or more than 3 per cent, between 1996 and 2020.
In Ecuador, much of the estimated 1,500 square kilometres of remaining mangrove forest is found in the provinces of Guayas and El Oro, according to one study. The once-forested channels in and around Samborondn and the neighbouring city of Guayaquil are now largely bare of vegetation, replaced by walls, jetties and promenades.
A cooperative strategy
To turn this tide, Samborondn launched a mangrove restoration project in 2024 that it hopes will inspire others in Ecuador and beyond to follow suit.
Leaders of the initiative bought 7,000 mangrove seedlings and hired farmers to help young volunteers to plant them in Guayaquil Historic Park. When they were done, the mangroves covered over 15,000-square-metres of riverbanks.
The seedlings were planted in a star-shaped pattern to encourage natural competition and the establishment of mangroves as they occur in nature in groups, says Edgar Muoz, Director of the Department of Environmental Management of the Municipality of Samborondn.
After some initial setbacks, a fringe of vegetation grew at the waters edge to prevent strong tides in the adjacent Daule River from washing the young mangroves away. The trees are now about a metre tall.
Community volunteers and park employees maintain the plot, removing plants that could out-compete the seedlings, while university students are monitoring progress. Spiders, crabs and birds are returning, while aphids and other pests are in retreat, Muoz says, signalling that the ecosystem is recovering.
The next phase of the project includes workshops on ecosystem restoration aimed at teachers, students and community members. To further raise awareness, students at the University of the Holy Spirit (known as UEES), which is in Samborondn, are creating a three-dimensional mangrove forest on the internet.
Online visitors will be able to walk among the trees, spotting wildlife and learning about the ecosystems and the many wonderful things they do for us, Muoz says.
For the municipality, the project is an important step toward its goal of restoring mangroves along the entire riverside of Samborondn. Another area has already been identified as suitable for planting.
Our commitment is to leave urban ecosystems in better condition than when we inherited them, ensuring a thriving environment for future generations, Muoz says.
Global wetlands
Samborondn is one of dozens of urban areas around the world receiving financial and technical support from a UNEP project to restore ecosystems and embed nature into urban planning processes.
Funded by the Government of Germany, the Generation Restoration project is part of the UN Decade on Ecosystem Restoration, a global initiative whose aims include helping countries deliver on their commitments to restore 1 billion hectares of degraded ecosystems.
Protecting and reviving wetlands is a priority for many municipalities. In Douala, Cameroons biggest city, local authorities, traditional leaders and others are teaming up to conserve mangroves. Iloilo, a city on Panay Island in the Philippines, is extending an effort that has returned mangroves to about 80 hectares of riverside land, including along its downtown esplanade. And communities in Overstrand, a municipality in South Africas Western Cape, are aiming to restore a peatland and estuary along the Ornus River that were degraded by flooding and invasive plants.
UNEPs Atallah said the projects demonstrate a growing appreciation of the importance of urban ecosystems.
People around the world are eager to rebuild the often massively degraded nature that surrounds them, she said. Hitching that desire to scientific insight and financial support will be key to achieving the kind of large-scale restoration that our planet urgently needs.
The UNEP Generation Restoration project, funded by the German Federal Ministry for Economic Cooperation and Development (BMZ), focuses on scaling up urban ecosystem restoration. Running from 2023 to 2025, UNEP, in collaboration with the UN Decade on Ecosystem Restoration and ICLEIs Global Biodiversity Centre, is working with 24 cities to address key political, technical, and financial challenges.The project has two key components:advocating for public and private investment in ecosystem restoration and job creation through nature-based solutions and empowering city stakeholders globally to replicate and scale restoration initiatives. This initiative stands as a contribution to the UN Decade on Ecosystem Restoration and the Global Biodiversity Framework.
The UN General Assembly has declared 20212030 a UN Decade on Ecosystem Restoration. Led by the UN Environment Programme and the Food and Agriculture Organization of the UN, together with the support of partners, it is designed to prevent, halt, and reverse the loss and degradation of ecosystems worldwide. It aims at reviving billions of hectares, covering terrestrial as well as aquatic ecosystems. A global call to action, the UN Decade draws together political support, scientific research, and financial muscle to massively scale up restoration.
The planet is experiencing a dangerous decline in nature. One million species are threatened with extinction, soil health is declining and water sources are drying up. TheKunming-Montreal Global Biodiversity Frameworksets out global targets to halt and reverse nature loss by 2030. It was adopted by world leaders in December 2022. To address the drivers of the nature crisis, UNEP is working with partners to take action in landscapes and seascapes, transform our food systems, and close the finance gap for nature.
